Heat exchanger

ABSTRACT

A heat exchanger according to some embodiments includes heat exchanger plates stacked one inside the other and each having a trough-shaped edge, flow ducts located between the heat exchanger plates for heat-exchanging media, feed ducts and discharge ducts, and an attachment plate having openings for feeding and discharging the media through the attachment plate. In some embodiments, a multipart attachment plate is provided, wherein a bottom heat exchanger plate lies on an attachment plate, and another overlying attachment plate has a cutout having an edge shaped to lie against the trough-shaped edge of the bottom heat exchanger plate.

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority is hereby claimed to German Patent App. No. 10 2006 022 445.0 filed on May 13, 2006, the entire contents of which are incorporated herein by reference.

BACKGROUND

German patent application DE 10 2004 003 790 A1 discloses a heat exchanger/oil cooler with a relatively thick base plate which is hollowed out in a trough shape in complex processing steps. The heat exchanger is inserted into this hollow shape, and then soldered to the base plate. This measure serves to avoid fractures in edge regions of the bottom heat exchanger plate due to thermal and mechanical stresses.

Furthermore, Japanese patent application JP 02-691155 discloses various options for strengthening the bottom plate of a heat exchanger. In addition to a stable base plate (such as that described above) provided with a trough shape in which a bottom heat exchanger plate is seated, strips are applied from the outside, and extend on the base plate and around the circumference of the bottom heat exchanger plate.

The two publications described above show relatively complex designs for reinforcement of bottom heat exchanger plates against the formation of fractures.

SUMMARY

Some embodiments of the present invention provide alternative, manufacturing-friendly solutions for heat exchangers having lower heat exchanger plates resistant to thermal and mechanical stresses.

In some embodiments, a multipart heat exchanger attachment plate is provided, wherein a bottom heat exchanger plate lies on an attachment plate and an attachment plate which is arranged above it has a cutout having an edge shaped to lie against the trough-shaped edge of the bottom heat exchanger plate.

In some embodiments, the edge of the cutout has a bending angle which corresponds to the angle of the trough-shaped edge of the bottom heat exchanger plate. The angle of the trough-shaped edge can be approximately 8 to 15°. The bending angle of the edge of the cutout can therefore exceed 90°, and in some embodiments is approximately 98 to 105°. The shaping of the edge can be made easier if the corners of the cutout are indented or cut out. In some embodiments, the attachment plate is embodied in three parts. In light of the design feature disclosed herein, it is possible to provide an attachment plate having an overall thickness no greater than that found in the prior art. Nevertheless, the thickness of each part of the attachment plate can be significantly greater than the thickness of the heat exchanger plates.

Also in some embodiments, the top attachment plate can have the cutout, and the attachment plates which are arranged below it can be formed in such a way that they are suitable for receiving seals.

Parts of the attachment plates can have marks so that they can be assembled more easily. Parts of the attachment plates can also have matching holes in order to be able to mount the heat exchanger.

In some embodiments, a seal is clamped between a bent-over opening edge of one attachment plate and a planar opening edge of another attachment plate. The seal can be placed under a degree of pre-stress so that the seal does not drop out of its position in the course of mounting. These measures can improve the ease of heat exchanger mounting.

In some embodiments, the cutout is smaller than the base surface of the heat exchanger plate before the shaping of the edge is carried out. The cutout and the base surface of the heat exchanger can, for example, be embodied as rectangles, with the four sides of the edge of the cutout running parallel to the four sides of the base surface.

Further advantages and features of the present invention (e.g., reduced materials) will be apparent from the following description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features of the present invention are described with reference to exemplary embodiments shown in FIGS. 1-5, wherein:

FIG. 1 shows a section through the lower region of a heat exchanger;

FIG. 2 shows a partial section through a heat exchanger of another exemplary embodiment;

FIG. 3 shows a plan view of an attachment plate used in FIGS. 1 or 2;

FIG. 4 shows another a plan view of the attachment plate of FIG. 3; and

FIG. 5 shows a view of the attachment plate opening shown in FIG. 2, viewed in the direction of the arrow in FIG. 2.

DETAILED DESCRIPTION

FIG. 1 shows a lower region of a heat exchanger 1, which is presented by way of example only as an oil cooler. The illustrated heat exchanger 1 is composed of a number of trough-shaped heat exchanger plates 10 which are stacked one inside the other. The heat exchanger plates 10 bear against one another at their outer edges 11 to form the heat exchanger 1, which is sealed by soldering or brazing. Alternating flow ducts 5 for two mediums flowing through the heat exchanger 1 are defined between the heat exchanger plates 10, which are shaped to define the flow ducts 5. In the flow ducts 5 it is possible, as is shown here, to provide turbulence inserts 6 for improved heat exchange, or to provide other elements or structure (not shown) for generating turbulence. In operation, media passes through the openings 21 in a part 3 of an attachment plate, and flows into and out of the heat exchanger 1 through feed ducts 22 and discharge ducts 20 (see arrows in FIG. 1). The media can also flow into and out of the heat exchanger 1 through connectors (not shown) so that four openings 21 are provided in the part 3 of the attachment plate if both media are conducted through the attachment plate 3. It should be noted that it is also possible to provide any other type of heat exchanger attached to a housing or engine block in a similar way. For example, it is possible to use screwed connections 30 passing through one or more attachment plates 3 (see FIG. 1) for the attachment process.

The number and positions of openings 21 in the attachment plate 3 are adapted according to requirements of the heat exchanger.

A higher likelihood of fractures often exists at the edge 11 of the bottom-most heat exchanger plate 10 due to thermal and mechanical stresses of the heat exchanger 1 during its use in a motor vehicle (for example). In order to avoid this, a cutout 26 is punched into an attachment plate 2 during its manufacture, and the edge 25 of the cutout 26 is bent over subsequently or simultaneously. The edge 25 of the cutout 26 can be bent in such a way that its end 27 covers to a greater or lesser extent approximately half of the edge 11 of the bottom-most heat exchanger plate 10, and bears directly against it. A bending radius for the edge 25 of approximately 98 to 105° can be produced, since the edge 11 of each heat exchanger plate 10 is bent outward away from a vertical orientation by approximately 8 to 15°. This reinforcement configuration at the bottom-most heat exchanger plate 10 (in region A of FIG. 1) can avoid stress fractures. At the same time, in this way it is possible to reduce the consumption of material without reducing the ability of the heat exchanger and heat exchanger mounting structure to withstand stress. In fact, the ability to withstand such stress can even be improved which achieving this material savings.

FIG. 2 shows another exemplary embodiment of the heat exchanger 1. Here, a three-part attachment plate is used, and includes parts 2, 3, and 4. Parts 2 and 3 can define seal receptacles at the openings 21, such as are described, for example, in patent application number DE 10 2006 005 084). With reference also to FIG. 5, in order to clamp the seal 41 tightly so that it does not drop out while the oil cooler 1 is being mounted, the opening 21 in the part 3 of the attachment plate can be, on the one hand, formed here in a corrugated shape, and on the other hand the opening 21 in the part 2 can be shaped to at least partially receive the seal 41 (e.g., by a nested relationship with the seal 41 and/or by a rolled shape 40 in which the seal 41 is received). In some embodiments, significant advantage can be obtained through the combination of the secured or retained seal 41 (e.g., by means of the particular shape 40 of the attachment plate) and reinforcement of the edge 11 of the bottom-most heat exchanger plate 10 by the bent-over edge 25 of the cutout 26 of the attachment plate part 4.

The individual parts 2, 3, 4 of the attachment plate can be manufactured from sheet metal plates of equal thickness or from sheet metal plates of different thicknesses. Overall, all the attachment plates 2, 3, 4 together can have a smaller thickness D in the region underneath the heat exchanger 1 compared to structures in the prior art, and in the rest of the region B can be equally thick (if desired). The parts 2 or 4 of the attachment plate can have a greater thickness than conventional heat exchanger plates in order to bring about particularly advantageous reinforcement. After bending over the edge 25 of the attachment plate 4, it may also be advantageous to improve the bearing of the edge 25 of the attachment plate cutout 26 against the edge 11 of the heat exchanger plate 10 in the bend 28 by post-processing, such as by notching or other operations.

FIG. 3 shows a plan view of the part 2 or 4 of either attachment plate shown in FIGS. 1 and 2. Part 2 or 4 of the attachment plate can have the appearance shown in FIG. 3 after the cutout 26 has been punched or made in any other manner. In order to avoid fractures in the corners 52 of the cutout 26 during shaping of the edge 25, the corners 52 can each be provided with an indent, notch, cut, or corner cutout 50 (collectively referred to herein as a “cutout”). When the edge 25 is bent over or deep drawn in some embodiments, a region 51 can be produced at the corners 52 of the cutout 26, at which region 51 an edge 25 of the cutout 26 does not bear on the edge 11 of the bottom heat exchanger plate 10 (see FIG. 4). However, depending on the requirements of the heat exchanger or environment, it is also possible to dispense with the cutouts 50, whereby a smaller material thickness can be obtained at the corners 52 than at the side edges 53 (not shown). Holes 30 can be formed in all the parts 2, 3, 4 of the attachment plate to serve as engine block or housing attachment locations for the completely soldered heat exchanger 1.

In some embodiments, all the parts 2, 3, 4 of the attachment plate have marks in order to facilitate the mounting process. 

1. A heat exchanger, comprising: a plurality of stacked heat exchanger plates, each having a trough-shaped edge; a plurality of flow ducts defined between the plurality of stacked heat exchanger plates and through which heat-exchanging media can flow; at least one feed duct; at least one discharge duct; an attachment plate defining a plurality of openings for feeding and discharging heat exchange media, the attachment plate having first and second portions, wherein a bottom-most heat exchanger plate of the plurality of heat exchanger plates lies on the first portion of the attachment plate, and wherein a second portion of the attachment plate defines an aperture having an edge shaped to lie against the trough-shaped edge of the bottom-most heat exchanger plate.
 2. The heat exchanger according to claim 1, wherein the edge of the aperture is oriented at an angle corresponding to an angle of the trough-shaped edge.
 3. The heat exchanger according to claim 1, wherein the attachment plate comprises two abutting parts.
 4. The heat exchanger according to claim 2, wherein the attachment plate comprises two abutting parts.
 5. The heat exchanger according to claim 1, wherein the attachment plate comprises a stack of three parts.
 6. The heat exchanger according to claim 2, wherein the attachment plate comprises a stack of three parts.
 7. The heat exchanger according to claim 1, wherein the edge of the aperture in the attachment plate comprises cutouts at the corners.
 8. The heat exchanger according to claim 2, wherein the edge of the aperture in the attachment plate comprises cutouts at the corners.
 9. The heat exchanger according to claim 5, wherein: the second portion of the attachment plate is defined by a top part of the stack of three parts, and at least partially defines the aperture; the first portion of the attachment plate is defined by middle and lower parts of the stack of three parts; and the first portion comprises additional apertures about which are received respective seals.
 10. The heat exchanger according to claim 6, wherein: the second portion of the attachment plate is defined by a top part of the stack of three parts, and at least partially defines the aperture; the first portion of the attachment plate is defined by middle and lower parts of the stack of three parts; and the first portion comprises additional apertures about which are received respective seals.
 11. The heat exchanger according to claim 5, further comprising a seal clamped between a bent-over edge of an additional aperture in a first part of the attachment plate and another edge of a second part of the attachment plate.
 12. A heat exchanger according to claim 6, further comprising a seal clamped between a bent-over edge of an additional aperture in a first part of the attachment plate and another edge of a second part of the attachment plate.
 13. A heat exchanger according to claim 9, further comprising a seal clamped between a bent-over edge of an additional aperture in the middle part of the attachment plate and another edge of the lower part of the attachment plate.
 14. A heat exchanger according to claim 10, further comprising a seal clamped between a bent-over edge of an additional aperture in the middle part of the attachment plate and another edge of the lower part of the attachment plate.
 15. A heat exchanger according to claim 1, wherein the aperture in the attachment plate is smaller than a base surface of the bottom-most heat exchanger plate before formation of the edge.
 16. A heat exchanger, comprising: a plurality of stacked plates each having a body and a peripheral edge oriented at an angle with respect to the body, the plurality of stacked plates each including a bottom-most stacked plate; a plurality of fluid flow channels defined between the plurality of stacked plates; an attachment plate having a body and an aperture defined therein, wherein edges of the aperture are oriented at an angle with respect to the body of attachment plate; wherein the bottom-most stacked plate is within the edges of the aperture in the body; and wherein the edges of the aperture in the body abut the peripheral edge of the bottom-most stacked plate.
 17. The heat exchanger according to claim 16, wherein the edges of the aperture exert a force against the peripheral edge of the bottom-most stacked plate.
 18. The heat exchanger according to claim 16, wherein the attachment plate comprises first and second stacked plates.
 19. The heat exchanger according to claim 18, wherein the bottom-most stacked plate rests upon the first stacked plate of the attachment plate; and the aperture is defined in the second stacked plate of the attachment plate.
 20. The heat exchanger according to claim 16, further comprising at least one seal received within a portion of the attachment plate. 